Suzuki DF 25 Service Manual page 249

5. Carefully pull out propeller shaft and housing to check tooth
contact pattern.
Optimum tooth contact
The optimum tooth contact is shown at right.
A shim adjustment may be necessary to obtain this contact
pattern.
The backlash of the gear should be checked when in-
creasing or decreasing the thickness of the shim to
adjust tooth contact.
Example(1)
Incorrect topside toe contact:
Correction measures:
• Decrease thickness of forward gear shim.
• Slightly increase pinion gear shim thickness.
Do not set tooth contact in this position (top side toe
contact). Damage and chipping of forward and pinion
gear may result.
Example(2)
Incorrect bottom side toe contact:
Correction measures:
• Increase thickness of forward gear shim.
• Slightly decrease pinion gear shim thickness.
Do not set tooth contact in this position (bottom side
toe contact). Chipping of pinion gear may result.
LOWER UNIT 10-25
Concave side
Convex side
Heel
Tooth top
Tooth bottom
Optimum tooth contact
approx. 1/3 of
tooth width approx.
HEEL
Convex side
EXAMPLE OF INCORRECT
Top side toe contact
HEEL
EXAMPLE OF INCORRECT
Bottom side toe contact
HEEL
Tooth width
Toe
TOOTH
CONTACT
PATTERN
1 mm
TOE
TOE
TOE